• 제목/요약/키워드: Variable Breadth

검색결과 18건 처리시간 0.018초

변화폭 원호형 띠기초의 자유진동 (Free Vibrations of Circular Strip Foundations with Variable Breadth)

  • 이병구;허영;이종국
    • 한국소음진동공학회논문집
    • /
    • 제14권3호
    • /
    • pp.230-235
    • /
    • 2004
  • This paper deals with the free vibration analysis of circular strip foundations with the variable breadth. Taking into account effects of both rotatory inertia and shear deformation, differential equations governing free vibrations of such foundations are derived. The Winkler foundation is chosen as the model of soil foundation. The breadth of strip foundation is assumed to be a linear function. The differential equations are solved numerically to calculate natural frequencies. In numerical examples, the strip foundations with the hinged-hinged, hinged-clamped. clamped-hinged and clamped-clamped end constraints are considered. The parametric studies are conducted and the lowest four frequency parameters are reported in figures as the non-dimensional forms.

Pasternak지반으로 지지된 변화폭 원호형 띠기초의 휨-비틀림 자유진동 (Flexural-Torsional Free Vibrations of Circular Strip Foundation with Variable Breadth on Pasternak Soil)

  • 이병구;박광규;강희종;윤희민
    • 한국강구조학회 논문집
    • /
    • 제19권5호
    • /
    • pp.539-548
    • /
    • 2007
  • 이 논문은 Pasternak지반으로 지지된 변화폭 원호형 띠기초의 휨-비틀림 자유진동에 관한 연구이다. 띠기초의 단면은 단면깊이는 일정하고, 단면폭은 1차식으로 변화하는 변화폭을 갖는 직사각형 단면으로 채택하였다. 띠기초의 지반은 Winkler지반에 전단층을 갖는 Pasternak지반으로 모형화하였다. 이러한 원호형 띠기초의 자유진동을 지배하는 상미분방정식과 경계조건을 유도하였다. 자유진동의 관성항으로는 휨관성, 회전관성 및 비틀림관성을 고려하였다. 상미분방정식을 수치해석하여 4개의 최저차 고유진동수를 산출하였다. 수치해석의 결과로 띠기초의 변수들이 고유진동수에 미치는 영향을 고찰하였다. 이 논문의 결과는 띠기초의 동적 설계에 매우 유용한 자료를 제공할 수 있을 것으로 기대된다.

변화폭 원호형 띠기초의 휨-비틀림 자유진동 (Flexural-Torsional Free Vibrations of Circular Strip Foundation with Variable Breadth)

  • 이병구;박광규;김권식;이승우
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2005년도 추계학술대회논문집
    • /
    • pp.764-767
    • /
    • 2005
  • This paper deals with the flexural-torsional free vibrations of circular strip foundations with a variable breadth. The breadth of strip foundation varies with the linear functional fashion, which is symmetric about the mid-arc. Differential equations governing free vibrations of such foundations are derived, in which Winkler foundation is considered as the model of elastic soils. Effects of the rotatory and torsional inertias and shear deformation are included in the governing equations. Differential equations are numerically solved to calculate the natural frequencies. In the numerical examples, the free-free end constraint is considered. Effects of the rotatory and torsional inertias and shear parameter on the natural frequencies are reported. Parametric studies between frequency parameters and various system parameters are investigated.

  • PDF

지식관리시스템의 수직적 확산과 수평적 확산에 관한 실증적 연구 (The Factors Affecting Breadth and Depth of Diffusion for Knowledge Management Systems)

  • 서창교;설진영
    • 지식경영연구
    • /
    • 제9권3호
    • /
    • pp.77-105
    • /
    • 2008
  • This study primarily aims at identifying what factors significantly affect the diffusion of knowledge management systems(KMS) and finding out how these identified factors can be effectively managed, especially for Korean companies. The research model is derived based on previous researches on innovation diffusion, information systems implementation, and KMS. The model is used to examine the role of determinants in influencing the extent to which KMS is diffused within organizations. Independent variables of this research are composed of technical characteristics, organizational characteristics and environmental characteristics. 'Breadth of diffusion' and 'depth of diffusion' concept are used to measure the extent of KMS diffusion which is the dependent variable of this model. The 101 companies of total 1,000 samples responded to the survey. To analyze tile results of this empirical study, we performed the multiple regression analysis. As a result, it was shown that the relative advantage, complexity, information system maturity, size, top management support, champion, competitive pressure have influences on both the breadth and the depth diffusions. On the other hand, the organizational culture, valuation and compensation, and uncertainty of environmental factors were not verified to be significant. This empirical study will provide Korean companies with insights into effective ways to diffuse the KMS and succeed in business competition.

  • PDF

The External Knowledge Utilization and Radical Innovation in Korea Electronic Industry

  • Lee, Youngwoo;Kim, Jae-Jin;Chang, Sul-Ki
    • 동아시아경상학회지
    • /
    • 제6권4호
    • /
    • pp.13-24
    • /
    • 2018
  • Purpose - This study investigates the moderation effect of internal factor, a firms size, on the external knowledge sourcing strategy and its effectiveness in generating radical innovation. We incorporate concepts of breadth and depth as two measures to gauge the degree of openness in firms external search Research design and methodology - The dependent variable in the regression model is the percentage of innovative sales and therefore, Tobit regression is employed for estimating significant factors affecting on the ratio of first-to-market by breadth and depth in external knowledge, internationalization, and size. Results - The results show that the external knowledge, in terms of both breadth and depth, has a positive relationship with radical innovation. However internationalization as external knowledge resources is not statistically accepted. Firm size has moderating effect on innovation negatively only in case of using external knowledge resources to a high degree. Conclusions - Firms obtain external information mostly from customers, competitors, and suppliers etc. empirical knowledge in terms of scope and intensity is an important contributor to innovation. And intensity use of external knowledge and information resources can work in favor of smaller firms rather than larger ones. Internationalization seems to have little effect on innovation but it requires further researches with clear criteria and more data.

경계조건 변화에 따른 Pasternak 지반으로 지지된 원호형 띠기초의 휨 자유진동에 관한 변수연구 (Parametric Studies of Flexural Free Vibrations of Circular Strip Foundations with Various End Constraints Resting on Pasternak Soil)

  • 이병구;이광범;강희종;윤희민
    • 한국소음진동공학회논문집
    • /
    • 제17권9호
    • /
    • pp.835-846
    • /
    • 2007
  • 이 논문은 Pasternak 지반으로 지지된 변화폭 원호형 띠기초의 휨 자유진동에 관한 연구이다. 단면폭은 띠기초의 중앙점을 중심으로 대칭 일차 함수를 갖는 변화폭으로 선정하였다. 이 연구에서 지반은 전단층을 갖는 탄성지반인 Pasternak 지반으로 모형화 하였고 회전관성과 전단변형을 고려한 곡선 띠기초의 자유진동을 지배하는 상미분방정식을 유도하였다. 이 상미분방정식을 수치해석하여 고유진동수 및 진동형을 산출하였다. 수치해석 예에서는 회전-회전, 회전-고정 및 고정-고정의 3개의 지점조건을 고려하였다. 띠기초의 무차원 변수들이 고유진동수에 미치는 영향을 분석하였다.

Some Aspects of Laying, Incubation and Hatching in the Great Reed-Warbler

  • Yoo, Jeong-Chil;Park, Yu-Seong
    • 한국생태학회:학술대회논문집
    • /
    • 한국생태학회 2002년도 VIII 세계생태학대회
    • /
    • pp.107-111
    • /
    • 2002
  • During the breeding season of 1998, breeding ecology of the Great Reed-Warbler (Acrocephalus arundinaceus orientalis) was studied at Yangsoo-ri and Yongdam-ri of the Yangpyung-gun, Kyunggi province, Korea. Egg-weight (CV: 6.25) was more variable than either length or breadth, and breadth was the least variable of the measures. Significant variations In overall egg-weight occurred between clutches, and that more of the total variation in egg-weight and shape are due to inter-clutch variation as to intra-clutch variation when the data were pooled. The last egg tends to be larger than the remaining eggs in the clutch of the Great Reed-Warbler, suggest- ing the Great Reed-Warbler may adopt the brood-survival strategy. When method 3 was used, the most common incubation period is 12 days. In the Great Reed-Warbler, the length of the incubation period was related to clutch-size when method 1 (r=0.485, p<0.05) and method 2 (r=0.621, p<0.01) were employed, but not related to egg weight. The average number of days of hatching asynchrony was 2.5, raging 0.5∼2.5. Asynchronous hatching was related to the clutch size (r=0.66, p<0.01). Hatching sequence was closely related to the laying sequence (r=0.93, p<0.001), suggesting Great Reed-Warblers incubate their eggs before clutch completion. The effect of egg weight on hatching asynchrony was found in Great Reed-Warblers (t-test, p<0.01).

  • PDF

한국 여고생의 표준치수 설정을 위한 연구 (II) (A Study of Establishment of the Standard Sizes for the High School Girls (II))

  • 손원교
    • 대한가정학회지
    • /
    • 제12권2호
    • /
    • pp.621-631
    • /
    • 1974
  • The objective of the study was to obtain standard sizes of body of the high school girls for designing clothes and developing pattern grading of clothes. In 1972, 342 students, selected by the stratified cluster random sampling method, at three high schools in Seoul were measured on forty-one items by the R. Martin method. Statistical techniques of mean, standard deviation, coefficient variable, maximum and minimum, range, t-test were utilized to analyze the data. The findings of the study were as follows ; 1. No differences were found among the age groups in the all measured variables. 2. Stature, bust girth, hip girth, acromion width, posterior waist girth/stature ratio of the high school girls were significantly smaller than those sizes of adult women. This result implies that those sizes will be increased as the students grow up. But upper arm girth, upper arm girth/bust girth ratio, and thigh girth/bust girth ratio were bigger than those sizes of adult women. Waist girth, thigh girth, total head height/stature ratio, acromion width/stature ratio, and foot length/stature ratio were nearly similiar to those of adult women. 3. According to the result of t-test, waist breadth, spinailiaca anterior height/stature ratio, thigh girth/bust girth ratio, and thigh/hip girth ratio of the 15 year old group were significantly different from those of the 16 year old group at the level of 0.05. Bust girth, weight, foot breadth, posterior croth length, and cervical height/stature ratio of the 16 year old group were significantly different from those of the 17 year old group at the level of 0.01. Hip girth, upper arm girth, waist breadth/stature ratio, and neck base girth/bust girth ratio of the 16 year old group were significantly different from those of the 17 year old group at the level of 0.05.

  • PDF

Experimental evaluation of back-to-back anchored walls by double-plates anchors

  • Amir, Najafizadeh;AmirAli, Zad
    • Geomechanics and Engineering
    • /
    • 제31권6호
    • /
    • pp.599-614
    • /
    • 2022
  • One of the methods of stabilizing retaining walls, embankments, and deep excavations is the implementation of plate anchors (like the Geolock wall anchor systems). Back-to-back Mechanically Stabilized Earth (BBMSE) walls are common stabilized earth structures that can be used for bridge ramps. But so far, the analysis of the interactive behavior of two back-to-back anchored walls (BBAW) by double-plates anchors (constructed closely from each other and subjected to the limited-breadth vertical loading) including interference of their failure and sliding surfaces has not been the subject of comprehensive studies. Indeed, in this compound system, the interaction of sliding wedges of these two back-to-back walls considering the shear failure wedge of the foundation, significantly impresses on the foundation bearing capacity, adjacent walls displacements and deformations, and their stability. In this study, the effect of horizontal distance between two walls (W), breadth of loading plate (B), and position of vertical loading was investigated experimentally. In addition, the comparison of using single and equivalent double-plate anchors was evaluated. The loading plate bearing capacity and displacements, and deformations of BBAW were measured and the results are presented. To evaluate the shape, form, and how the critical failure surfaces of the soil behind the walls and beneath the foundation intersect with one another, the Particle Image Velocimetry (PIV) technique was applied. The experimental tests results showed that in this composite system (two adjacent-loaded BBAW) the effective distance of walls is about W = 2.5*H (H: height of walls) and the foundation effective breadth is about B = H, concerning foundation bearing capacity, walls horizontal displacements and their deformations. For more amounts of W and B, the foundation and walls can be designed and analyzed individually. Besides, in this compound system, the foundation bearing capacity is an exponential function of the System Geometry Variable (SGV) whereas walls displacements are a quadratic function of it. Finally, as an important achievement, doubling the plates of anchors can facilitate using concrete walls, which have limitations in tolerating curvature.

남성 재킷 패턴 설계에 관한 연구 (A Study on the Design of Men's Jacket Pattern)

  • 이원자;김진선
    • 복식문화연구
    • /
    • 제12권6호
    • /
    • pp.953-970
    • /
    • 2004
  • The purpose of this study was to design men's jacket pattern for variable body types by employing the data of wearing evaluation from experimental basic bodices selected by male subjects in the 30's. As a result of sensory evaluation, functional test and clothing pressure test by each type of experimental basic bodices, the 3rd experimental basic bodice was chosen to be a basic bodice type in this research since it showed a high degree in fitness and function, but a low in the clothing pressure test. As a comparison of one item from conventional jacket and sleeve pattern with each somatotype, the type 2(the standard somatotype) indicated a great fitness in both basic bodice type and conventional jacket pattern, whereas the type 1 and the type 3 showed higher fitness and moving function in the basic bodice type. In the making of men's jacket, many corrections were made in the front interscye breadth, back interscye breadth, front and back length, and shoulder line as adapting each body type. Thus, the ease-amount of chest circumference at scye for clothes should be established differently according to the size of chest circumference at scye.

  • PDF